Looks like it could be a sand cast counterfeit, but is also possibly a quarter struck on a quarter size planchet made from dime stock, which would be thinner. This would be known as a "wrong stock error" - and they are known to exist for a number of different issues....whether they are known for 1937 quarters is beyond my scope of study.
How about the sound of the coin? Does it ring like a struck coin, or does it have a more lead-like or pewter-like "dead" noise?
Can you take edge comparison photos of the two coins?
How about the sound of the coin? Does it ring like a struck coin, or does it have a more lead-like or pewter-like "dead" noise?
Can you take edge comparison photos of the two coins?



















